Thanks for the all the advice in this thread, but none of the above worked for me, after spending half a day trying it all.
Got this advice from the horse's mouth (Samsung).... Worked for me. Now I'm back into Kies (for what it's worth);
Hope it helps:-
What probably happened is the USB drivers for mobile phones did not get updated along with Kies after the automatic/prompted update. Please follow the steps below in order to rectify this issue:
- First, ensure Kies is not open and disconnect any connected devices from the PC
- Go to Start > Control Panel > Add/Remove Programs OR Uninstall a Program
- In the list, locate Samsung USB Drivers for Mobile Phones then click uninstall or remove
- When the uninstall is complete, launch Kies This took over an hour for me
- In Kies, click Tools > Troubleshoot Connection Error then click start
- When this process is complete, click Complete
- Turn the device off then back on to refresh the driver data. Alternatively, hold down the HOME key on the phone, tap the button to enter Task Manager, tap the RAM tab, then 'Clear Device Memory'.
- Ensure USB debugging is off on the device via Settings > Applications > Development
- Return the phone to the home screen, ensuring it is 'awake' but idle at the home screen, then reconnect the device.
- Please note that is may take several minutes for Kies to recognise the device - Windows will always recognise the device before Kies does as it has to install additional drivers from device memory.